This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We seek to better characterize the relationship of the presence of circulating tumor cells (CTCs) in urothelial and renal cell carcinoma models. While CTCs have been studied extensively in breast, colorectal and prostate cancer;very little is known about its prognostic and therapeutic correlation in urothelial and renal carcinoma. We propose to analyze peripheral venous blood samples in patients presenting to our clinic with Transitional Cell Carcinoma (TCC) or Renal Cell Carcinoma (RCC) undergoing chemotherapeutic or surgical treatment for clinical stage T2 disease or greater.